Wall bed



Jan. 5, 1937;

E. H. BRIDENBAUGH 7,1 6

WALL BED Filed Feb. 2, 1953 4 Sheets-Sheet 2 /Z6//3 E 2/ 2/ FTC-LL 7ATTORN Jan. 5, 1937. E. H. BRIDENBAUGH 2,067,136

v WALL BED Filed Feb. 2, 1933 4 Sheets-Sheet 3 Jan. 5, 1937. E. H.BRIDENBAUGH 2,067,136

WALL BED Filed Feb. 2, 1933 4 Sheets-Sheet 4 I ATTO Y.

Patented Jan. 5, 1937 SA'E'E 'l' QFFICE WALL BED Elmer H. Bridenbaugh,

Denver, 0010., assignor,

Application February 2, 1933, Serial No. 654,852

14 Claims.

My invention relates to improvements in wall beds, the operation ofwhich is fully automatic save for the closing of an electric circuit,and consists primarily of a hydraulic power unit actuated by a fluid,under pressure, in association with other suitable mechanicalconstruction.

Briefly, my invention embodies a bed pivotally mounted at one end bymeans having a conjunctive operative relation to a primary pivotalshaft, on one end of which is disposed in fixed relation thereto, anoscillating quadrant type piston enclosed in a suitable pressurechamber, the piston being actuated by a fluid, preferably oil, underpressure, through the medium of an electrically operated hydraulic pump.

The primary object of my invention is to provide a wall bed with meansfor its operation from and to a closed position, by the simple act ofclosing an electric circuit, thereby obviating strenuous physicalexertion and danger of accident or injury to the operator.

Another object of primary importance of my invention is to provide awall bed with such mechanical construction and safety devices that canbe so minutely adjusted relative to the weight of the bed, that anyadditional weight will automatically cause the bed to become, or remainstationary.

Another object of my invention is to provide a wall bed with uniform,quiet and positive application of power, and means for regulating thedegree of application of said power, to the extent of operating the bedassembly only, which assembly inciudes a fully made up bed ready foroccupancy.

Another object of my invention is to provide suitable constructionthroughout so that space occupied by the same is well within theconserved and conventional space for the wall type of bed.

Another object of my invention is to provide means for positivelyremoving application of power at the termination of either the up or thedown stroke, except at the will'of the operator.

Another object of my invention is to provide means whereby if anyobstruction comes in the path of the beds course of travel, either up ordown, it will remain stationary until such obstruction is removed, inwhich event the bed will continue to the full limit of its movementwithout endangering any of its mechanism.

Another object of my invention is to provide suitable mechanism workingin conjunction with the power unit whereby the bed may be manuallyoperated, in case for any reason it is desired to do so.

Another object of my invention is to provide a suitable fluid reservoirfor the hydraulic unit, and means associated therewith for constantlykeeping the pressure chamber fully charged with said fluid.

Another object of my invention is to provide an efficient and positiveleverage mechanism operable in such a manner as to cause the bed andsaid leverage mechanism to occupy a minimum space in the closedposition.

In the following detailed description of my invention, reference is madeto the accompanying drawings, which form a part hereof, and in whichlike reference characters refer to like parts in all views throughoutthe description.

In the drawings:

Fig. l is a side elevation view of the bed in broken away section,showing the same in its open position; Fig. 2 is a side elevation viewof the bed, with parts broken away, showing the same in opened position;Fig. 3 is a side elevation view of the bed in broken away section,showing the same in closed position; Fig. 4 is an end view in crosssection of the bed, taken on the line 4-4 of Fig. 1; Fig. 5 is avertical cross section view of the hydraulic pressure chamber; Fig. 6 isa vertical cross sectional view taken on the line 66 of Fig. 5; Fig. 7is a sectional view taken on the line l'i of Fig. 6; Fig. 8 is avertical cross sectional View of the hydraulic pump and the mechanismfor controlling the pressure of the fluid within the hydraulic pressurechamber; Fig. 9 is a cross sectional view of the hydraulic pump taken onthe line 9-9 of Fig. 8; Fig. 10 is a cross section view taken on theline iii-4U of Fig. 8; Fig. 11 is a cross-section view taken on the lineH-ll of Fig. 8; Fig. 12 is a cross section view taken on the line l2-|2of Fig. 8; Fig. 13 is a fragmentary view of the pivotal base of the bedtaken on the line I3I3 of Fig. i, and showing the arrangement of thecounterbalancing springs, and Fig. 14 is a fragmentary cross sectionview of the pivotal base of the bed taken on the line l4l4 of Fig. 4.

Let the numeral I6 represent the bed assembly consisting of head, footand side rail members, which is of ordinary construction for a wall typebed except in its adaptation to my invention, which will be apparent inthe following specification. This bed is provided with a foot piececonsisting of two members I! and Ila, pivoted together as shown at I8,permitting the member I! to swing on its pivot to a position parallelwith the frame of the bed when the latter is in the closed position. Themember I? of the foot piece is connected by means of a telescoping rodIS with the base 24 of the bed, as shown at 22, the member 23 of whichis pivotally connected with the member l'i, as shown at 26, and themember 20 of which is pivotally connected with the base iii of the bed,as shown at 22. This telescoping rod enables the latter to be shortenedor lengthened, as the case may be, when the bed is closed or opened.

The bed It is also provided with a head piece of similar constructionand operation as that of the foot piece just described, and consists ofmembers 2! and 28 pivotally joined at 29, as illustrated in Figs. 1 and3. A telescoping rod, consisting of male and female members 3i and 32,connects the member 2? of the head piece with the wall, whereby saidmember is held in vertical position when the bed is in its openedposition. This telescoping rod is pivotally connected with the member2?, as shown at 3 3, and at its other end with the wall, as shown at Ma,thus enabling said rod to swing to the position shown in Fig. 3 when thebed is closed.

A housing designated in its entirety by the numeral 35 and forming ahydraulic pressure chamber, is rigidly secured to the base ill of thebed, and in which chamber there is operable a piston designated in itsentirety by the numeral 35. This piston is secured in fixed relation toa shaft 37 by means of a spline 38. This shaft 37 extends the entirewidth of the base 2i of the bed so that when the piston as is operatedthe bed will be moved by the rotation of the shaft 3'5 to the open orclosed position, depending upon the direction in which the piston 35 isactuated.

There are located in the housing of the pressure chamber 35,passage-ways 39 and do, through which the fluid, preferably oil, willcirculate in the manner hereinafter described, for actuating the piston36. When the bed is moved to its opened position the fluid will beforced under pressure through the passageway 33, behind the piston 36,causing the latter to move to the dotted line position, as shown in Fig.5, and actuate the bed to the opened position. Now, when it is desiredto close the bed, the fluid is caused to flow under pressure through thepassageway so behind the piston 36, and causes the latter to moveupward, rotating the shaft 3i, and carrying the entire bed with suchmovement to its closed position.

Sector shaped blocks 4| and 42 are arranged within the pressure chamber35 on opposite sides of the stem 33 of the piston 36, for sealing thepressure chamber 35 against leakage around the axis of the piston, Thepiston proper is provided with suitable packing M on its outer end andopposite edges, which tightly engages the walls of the chamber 35 underpressure through the medium of springs 45, thereby preventing leakage ofthe fluid around the edges of the piston.

A pump housing 45 is secured on top of the pressure chamber housing 35,as more clearly shown in Figs. 8 and 9, and is provided with passages iland is, which respectively register and communicate with the passages 39and ii? of the pressure chamber housing. A pump is arranged within thishousing as shown in Figs. 8, 9 and 12, and is provided with gear typepistons 9 and 50, which mesh with each other, as more clearly shown inFig. 8. The gear 9 is the driving gear and is fixedly secured upon adriving shaft 50*,

the latter being directly connected with and operable by the armature ofan electric motor 5|. The driven gear 50 of the pump is fixedly securedupon a shaft 52 journaled in the pump housing 58. This pump housing isin separable parts which are tightly secured together and sealed againstleakage of the fluid by means of bolts 53. Further description of thishousing appears to be of no advantage in this specification, except suchas may be necessary in relation to the invention as a whole, which willbe given in its proper connection.

The pressure chamber in the housing 35, together with the passageways G7and 58, as well as the chamber in which the pump gears 59 and 50 arearranged are all constantly filled to capacity with oil, which may bereplenished whenever necessary from a reserve tank 5 3 through theopening of a valve 55, whereby the oil will be replenished by gravityflow.

The passageways 41 and 48 are separated from each other through themedium of a partition 56, compelling the circulation of the oil throughthe chamber, designated by the numeral 5?, in which the pump gears 49and 5B are arranged. One wall of this chamber 51 is provided with a port58, located below the journals of the gears 49 and 59, and communicatingwith the passageway 7, and the opposite wall of said chamber is providedwith another port 59 located above the journals of said gears, andcommunicates with the passageway d8. Through these ports 58 and 59, theoil is forced alternately through the passageways d! and 48, dependingupon the direction of rotation of the gears t9 and 50. To illustrate,when said gears are rotating in the direction of the arrows in Fig. 8,the oil is being forced through the port 58 and passageways ll and 39,behind the piston 36, thereby actuating the latter to move the bedthrough the medium of the shaft 37 to its opened position, after whichthe piston will occupy the dotted line position, shown in Fig. 5. Now,assuming that the bed is in the opened position, and it is desired toactuate the same to the closed position, the electric motor 5! isrotated in such a direction as to cause the gears 59 and 59 to rotate inthe direction opposite that shown by the arrows in Fig. 8, therebyforcing the oil through the port 59 into the passageways it and 49 tothe rear of the piston 36, and the pressure thereby created actuates thesaid piston to the full line position, as shown in Fig. 5, causing theshaft 31 to rotate therewith and move the bed to the closed position.

On one side of the housing of the pressure chamber 35 there is located ahousing 60, in which is located an electric switch 61 into whichelectrical conductors within the cables 62 and 63 lead. This switch 6!is of the ordinary circuit make and break type, and need not bedescribed or shown in further detail.

Through the medium of a switch lever 64, the mechanism of the switch 6!is operably connected with a slide bar 65, as shown at 66. The oppositeends of this slide bar 65 are pivotally connected, as shown at 67 and68, respectively, to links 59 and 10, each of which forms the arm of abell crank lever, fixedly secured upon shafts TI and i2, journaled inthe housing of the pressure chamber 35, through the medium of journalboxes l3 and i l, set in the housing of the pressure chamber 35, one ofwhich is shown in detail in Fig. 6. The other arms i5 and 16 of thesebell crank levers are respectively secured to the -75 shafts H and 12.and occupy positions within the pressure chamber 35, so that they willbe engaged by the piston 36, whereby the bell crank levers will beactuated to move the slide bar 65. The movement of this slide bar 65actuates the switch 6| to stop the rotation of the motor and to set theswitch for the rotation of the motor in the opposite direction when theelectric current is applied through the medium of a switch Tl, operableto cause the motor 5! to rotate in either direction. In other words, ifthe bed is in its closed position, this slide bar 65 has been actuatedto shut off the current to the motor and to set the switch so that themotor will rotate in the direction to move the bed to the open positionwhen current is applied by actuation of switch ii, and vice versa.

By the use of a specially constructed and applied relief valve, thepressure of the fluid, under operation of the pump, may be equalizedagainst both sides of the piston 36, causing the latter to remainstationary, and the bed likewise to remain stationary at any position inthe path described by the opening or closing movement of the latter.This relief valve consists of a hollow nipple I8 threaded at its lowerend into a female casting 19 mounted on top of the pump housing 46, andwhich casting is provided with passageways 89 and 8! communicating withthe gear chamber 57 at their lower extremities and with the interior ofa valve housing 82, which said housing is received by the nipple l8, andengaged by the lower end of the latter with a flange 83 formed on thebottom of the valve housing 82. This flange 83 rests upon a disc valveseat 84, and by the threaded connection 85 of the nipple 8 with thefemale casting :9, the disc valve seat 8d is held against displacement,and also a tight joint is effected thereby to prevent the leakage of thefluid therethrough. To the top of the nipple 18 there is threaded a cap85 having integrally formed thereon a hollow stud 91, which is providedwith exterior threads 88. There is threaded upon this stud 8'! anadjustable thumb nut 89, which is held in its adjusted position by meansof a lock nut 99, also threaded upon the stud 8! below the thumb nut 89.A tension screw 91 passes through the top of the thumb nut 89 and iskeyed in fixed relation to the latter by means of a spline 92 so thatboth the thumb nut 89 and the tension screw 91 turn together. Thistension screw also passes through the hollow of the stud 8'! and cap 86into the nipple l9, and is threaded at its lower end, as shown at 93,into a cross-head 94, which is vertically movable within the nipple 18by means of the operation of the tension screw 9!. The top of thiscross-head 94 is provided with a flange 95, which has a slot thereinthat receives a spline 99, and by means of which the cross-head 94 isprevented from rotating under adjustment of the tension screw 9|,although permitted to move in a vertical direction. The tension screw 9|is provided with a circumferential flange b, which engages with asuitable packing 0, held in place between the cap 86 and the top of thenipple 78, whereby leakage of the fluid through the cap or around thetension screw is prevented.

The cross-head 94, below the flange 95 thereof, is of sufficient lessdiameter than the housing formed by the nipple 18, whereby space ispermitted to receive the upper end of a spiral tension spring 91. Theupper end of this spiral tension spring 91 is engaged with the flange 95of the cross-head 94, while the lower end of said spring is engaged witha disc 98, which has an opening 99 in the center thereof to receive thelower end of the tension screw 95, and thereby permit the movement ofthe disc 98 in a vertical direction against the tension of the spring97, for the pur- ,pose hereinafter described.

At the lower part of the hollow casting 79, the passageways ll and d8communicate with elongated chambers 99 and mi), respectively, which saidchambers are formed by the partition 56. The valve seat 85 is arrangedimmediately above these elongated chambers 99 and Hill, andcommunication established with the interior of the valve housing 82through the ports 30 and 8!, which respectively are arranged above thechambers 99 and H39. There are also provided in this valve seat 8%,ports lfii and i112, respectively positioned above the chambers 99 andH38. These ports ml and 92 are normally closed by ball valves Hi3 andH24, which are held seated by means of stems I95 and 59S, looselyengaging the said ball valves Hi3 and EM. These valve stems pass throughperforations in the top of the housing 82 and engage with the bottom ofthe disc 93. the spring 9? against the disc 98, the valve stems H35 andit are pressed downwardly against the ball valves )3 and H34, holdingthe latter firmly seated and closed against any minimum predeterminedpressure of the fluid created by the pump. Pins IE3? and H38 are setvertically within the valve housing 82 and operate as guides to preventdisplacement of the ball valves E33 and 94.

The predetermined pressure by which these valves E93 and I94 are openedmay be determined by adjustment of the tension screw 9|, and con sequentupward or downward movement of the cross-head 94. Now then, we willassume that the bed is in the opened position, and that a person orother abnormal weight is thereon, and we will also assume that theelectric motor 5i and the pump gears 49 and 59 are in operation forcreating pressure of the fluid behind the piston 36, the latteroccupying the position as shown by dotted lines in Fig. 5. The operationof the piston 36 under the influence of the pressure of the fluid thuscreated, will be negatived under the influence of the person or otherabnormal weight upon the bed, and will overcome the tension of thespring 91, forcing in this case the valve I94 open and permitting thefluid to pass through the port l iii into the chamber 579 and thencethrough passageways 4i and 3% to the opposite side of the piston 36,thereby equalizing such pressure and permitting the operation of thepump without actuating the piston 38, the fluid being by-passed. Now,assume that there is some obstruction to prevent the opening of the bed,such as coming in contact with a chair or some other article offurniture. The relief valve mechanism would again come into operation topermit the continued rotation of the electric motor, as well as the pumpgears 49 and 50, and to permit the piston 36 to remain stationary. Insuch case the valve E95 would open against the tension of the spring9'1, and the fluid be permitted to escape ,through the port 86 and theport 1:12 into the chamber I08 and thence through passageways 48 and 69to the rear of the piston 36, thereby equalizing the pressure on bothsides of this pis ton and causing the latter to remain stationary.

The gear and leverage mechanism and operation thereof is in exactduplicate on both sides of the bed, and therefore the same referencecharacters will be used to designate the duplicate parts Under theinfluence of the tension of iii) thereof, and will be referred to in thesingular, particular reference being made to Figs. 2 and 3.

A driven gear its is secured to the frame of the bed by means of bolts,or rivets i it, and this gear I89 meshes with another driving gear iii.The driving gear Hi is fulcrumed upon a bar Hi2, pivoted at its lowerextremity to the base of the bed 2 l as shown at i3, and the upper endof said bar H2 is pivotally connected with the driving gear ill, asshown at lid. The driven gear N39 is fulcrumed in a similar manner upona bar I I5, the lower end of which is pivotally connected with the baseM of the bed, as shown at H6, and the upper extremity thereof pivotallyconnected with the driven gear Hi9, as shown at I ll. These two fulcrumbars H2 and M5 are connected together by means of a cross bar l i ii,pivotally connected with the two fulcrum bars, as shown at H9 and i253.This connecting bar li-Si operates to hold the two gears Mil and iii inmeshing relation, and also to add stability to the fulcrum arrangement.

By reason of the foregoing described fulcrum arrangement, in itsrelation to the power transmitting shaft 3'5, the bed is moved at rightangles to its axis simultaneously with the movement of the bed to itsopened and closed positions, and as a consequence thereof the weightbeing carried is lessened as the bed is being moved to the closedposition, and of course the strain incident to the carrying of a heavyload is being diminished during the entire movement of the bed to theclosed position. Also, by reason of such fulcrum arrangement, as the bedis moved to its closed position the leverage mechanism is movedrearwardly into the wall compartment, and the bed proper drawndownwardly in a vertical direction, and moved rearwardly, or laterallyof the axis of the bed, to a position well within the wall compartment,thereby conserving space to the minimum degree, and obviating thenecessity of relatively larger compartment space to provide room for theoperation of the fulcrum mechanism.

An eccentric arm 52! is secured in fixed relation to the shaft 3i asshown at !22, and the opposite end thereof is pivotally connected withthe lower extremity of a link are, and the upper extremity of the link92 3 is pivotally connected with the gear HI, as shown at i25. Therotation of the shaft 37 actuates the eccentric arm HI, and through themedium of the link i2 5 causes the gears Hi] and H! to rotate in meshingrelation for opening or closing the bed, as the case may be.

The gear iii is provided with an integrally formed arm 425 to the outerextremity of which a bar E26 is pivotally connected, as shown at 52?,and the other end thereof pivoted as shown at I28, to an eccentric armE23, which is secured in fixed relation with a right angular shapedcounter balancing bar 535, journaled at its opposite ends in the base 25of the bed as shown at lid and extending parallel with the axis of thebed, or the shaft 3?.

Horizontally disposed spiral springs Hi8 are arranged transversely ofthe base of the bed, and connect the counterbalancing bar its with aparallel arranged stationary bar E32. These spiral springs MG, exertingtheir influence through the medium of the counterbalancing bar E35,eccen tric arm I29, bar H26 and the gear l l Loperate to counterbalancethe bed and to cause an even, uniform movement of the latter to theopened and closed positions, and to reduce vibration in the operation ofthe various parts of the bed. When the bed is being actuated to itsopened position,

the tension upon these springs I4!) is being increased, and the saidsprings are being relieved of tension as the bed is moved to its closedposition.

An arch shaped guide and brace member I 33 is secured to the base 2! ofthe bed, and the fulcrum bars I i2 and 525 are arranged upon oppositesides thereof. This arch shaped guide and brace member its is providedwith spaced apart stop pins HM adapted to be engaged by the fulcrum barI I2, whereby movement of the latter in either direction is limited.

The fulcrum bar H5 is provided with an integrally formed arm I36extending at right angles to the pivot l is of said bar, and adapted tooperatively engage with a stud E3! on the eccentric arm i2 5,intermediate the extremities of the latter. The outer extremity of thearm I36 is provided with a curve 538, concentric with the shaft 31,which is in constant engagement with the stud 53?, and this curved edgeterminates in a half circular recess E39, into which the stud I3! isreceived when the bed has reached the limit of its closing movement.Through the operation and shape of this arm i36, in its relation to theeccentric arm 52!, engagement of the stud I37 with the recess use whenthe bed has reached the limit of its vertical movement towards theclosing position acts to impart to the latter a sudden thrust to acompletely closed position and there firmly hold the assembly.

While there has been described and illustrated herein a specific formand application of the invention, it is understood that the same is notlimited thereto and that modifications and variations thereof may bemade without departing from the spirit of the invention or the scope ofthe appended claims.

Having thus described the invention, what I claim and desire to secureby United States Letters Patent is:

1. In a wall bed, the combination of means for actuating the bed,comprising a driving shaft, 2. driving gear operatively connected withsaid driving shaft, a driven gear mounted on the frame of said bed andmeshing with said driving gear, fulcrum bars upon which said driving anddriven gears are pivoted, and power transmission means connected withsaid driving shaft.

2. In a wall bed, the combination of means for actuating said bed to itsopened and closed positions, comprising a driving shaft, a driving gearoperatively connected with said driving shaft, 2. fulcrum bar pivoted atone end, said driving gear being journaled to the opposite end of saidfulcrum bar, a driven gear fixedly secured to the frame of the bed andmeshing with said driving gear, a second fulcrum bar pivoted at one end,said driven gear being journaled to the opposite end of said last namedfulcrum bar, and means connecting the first named fulcrum bar with thelast named fulcrum bar for holding said driving gear and said drivengear in meshing relation.

3. In a wall bed, the combination of means for actuating said bed to itsopened and closed positions, comprising a driving shaft, 2. driving gearoperatively connected with said driving shaft, a fulcrum bar pivoted atone end and upon the opposite end of which said driving gear isjournaled, a driven gear fixedly secured to the frame of the bed andmeshing with said driving gear, a fulcrum bar pivoted at one end andupon the opposite end of which said driven gear is journaled, said lastnamed fulcrum bar having an operative connection with said driving shaftwhereby when the said shaft has ceased its'operation the bed is heldfirmly in closed position.

4. In a wall bed, the combination of means for actuating said bed to itsopened and closed positions, comprising a driving shaft, a driving gear,an eccentric arm mounted on said driving shaft, a link pivotallyconnecting said eccentric arm with said driving gear, a driven gearfixedly secured to the frame of the bed and meshing with said drivinggear, and counterbalancing means operatively connected with said drivinggear and adapted to be actuated by the rotation of the latter.

5. In a wall bed, the combination of power transmitting means foractuating said bed to its opened and closed positions, comprising adriving shaft operatively connected with said power transmitting means,a driving gear operatively connected with said driving shaft, a drivengear fixedly secured to the frame of the bed and meshing with saiddriving gear, fulcrums upon which said driving gear and driven gear arerespectively pivoted whereby the positions of the axes of the pivots ofsaid gears are moved while said gears maintain their meshing relation toeach other, and counterbalancing means operatively connected with saiddriving gear and adapted to be actuated by the rotation of the latter.

6. In a wall bed, a combination of means for actuating the bed to itsopened and closed positions, comprising a power transmitting shaft, adriving gear operatively connected with said driving shaft, a fulcrumupon which said driving gear is pivoted whereby the position of the axisof the pivot of said driving gear moves with the movement of the bed,and tension means operatively connected with said driving gear.

7. In a wall bed, the combination of means for actuating said bed to itsopened and closed posi tions, comprising a journaled shaft, a drivinggear operatively connected with said shaft, a fulcrum upon which saiddriving gear is journaled, a separately-fulcrumed driven gear fixedlysecured to the frame of the bed and meshing with said driving gear, andmeans for transmitting power to said shaft. 7

8. In a Wall bed, the combination of means for actuating the bed to itsopened and closed positions, comprising a driving shaft, a driving gearoperatively connected with said driving shaft, a driven gear fixedlysecured to the frame of said bed and meshing with said driving gear, afulcrum bar pivoted at one end and upon the opposite end of which saiddriven gear is journaled, and an arm fixed to said fulcrum bar and opeable through engagement with an element fixed to said driving shaft tothrust the bed to a firmly closed position.

9. In a wall bed, the combination of a pivotally mounted driven gearfixedly secured to the bed frame and adapted to rotate about its pivotto actuate the bed, a power transmitting shaft, a pivotally mounteddriving gear operable by said shaft and adapted to rotate in mesh withsaid driven gear, and interconnected fulcrum bar supports for said gearsengageable by an element fixed to said shaft for variation in thepositions of said gear axes in progressive relation with the movement ofsaid bed.

10. In a wall bed having a power transmitting shaft, a driving gearjournaled eccentrically to said power transmitting shaft, crank means onsaid shaft link-connected with said driving gear and a driven gear fixedto the bed frame in meshing relation with said driving gear,counterbalancing tension means link-connected through independentlypivoted bell-crank means with said driving gear and operable throughrotation of the latter to exert greater counterbalancing ten sion as thebed is moved to its opened position.

11. In a wall bed, the combination of a pivotally mounted driven gearfixedly secured to the bed frame and adapted to rotate to actuate thebed, a power transmitting shaft, and a compound fulcrum connectingbetween said shaft and said driven gear operable to vary the position ofthe pivot of said driven gear in supplemental relation with the movementof said bed during that portion of the bed actuation adjacent but onelimit of its range of travel.

12. In a wall bed, the combination of a pivotally mounted driven gearfixedly secured to the bed frame and adapted to rotate about its pivotto actuate the bed, a power transmitting shaft, means operable totransmit rotation of said shaft to effect rotation of said gear, and acompound fulcrum connection between said shaft and said driven gearoperable to vary the position of the axis of the pivot of said drivengear during a fractional portion of and adjacent but one limit of therotation of said driven gear.

13. In a wall bed, the combination of a pivotally mounted driven gearfixedly secured to the bed frame and adapted to rotate about its pivotto actuate the bed, means operable to rotate said gear, and compoundfulcrum means supporting said gear axis and operable through engagementwith said gear rotating means to move said gear axis in supplementalrelation with the bed movement during a fractional portion of the bedactuation adjacent but one limit of its range of travel.

14. In a wall bed, the combination of a pivotally mounted driven gearfixedly secured to the bed frame and adapted to rotate about its pivotto actuate the bed, means operable to rotate said gear, and compoundfulcrum means supporting said gear axis and operable through engagementwith said gear rotating means during a fractional portion of its rangeof travel to vary the position of said gear axis adjacent but one limitof said gear rotation,

ELMER H. BRIDENBAUGI-I.

